Struts2方法调用的三种方式(有新的!调用方法的说明)

在Struts2中方法调用概括起来主要有三种形式

第一种方式：指定method属性

<action name="heroAction" class="com.ABC123.HeroAction" method="add">
            <result name="add">/add.jsp</result>
        </action>

　　这样Struts2就会调用heroAction中的add方法。

第二种方式：动态方法调用(DMI)

用这种方法需要设置一个常量

struts2的2.3以上版本的jar包 必须配置DMI

<constant name="struts.enable.DynamicMethodInvocation" value="true" />

　　

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.1//EN" "http://struts.apache.org/dtds/struts-2.1.dtd">
<struts> 

	<constant name="struts.enable.DynamicMethodInvocation" value="true" />  

<package name="goToEat" namespace="/" extends="struts-default">

	<action name="heroAction" class="com.ABC123.action.HeroAction" >
	<result name="list" >/list.jsp</result>
	<result name="gotoupd" >/upd.jsp</result>

	<!-- 重定向-->
	<result name="add" type="redirect">heroAction!list.action</result>

	</action>

	</package>

</struts>

　　动态方法调用是指表单元素的action并不是直接等于某个Action的名字，而是以如下形式来指定Form的action属性

<!-- action属性为action!methodName的形式 -->
        action = "action!methodName.action"

　　在struts.xml中定义如下Action

<package name="goToEat" namespace="/" extends="struts-default">

	<action name="heroAction" class="com.ABC123.action.HeroAction" >
	<result name="list" >/list.jsp</result>
	<result name="gotoupd" >/upd.jsp</result>

	<!-- 重定向-->
	<result name="add" type="redirect">heroAction!list.action</result>

	</action>

	</package>

　　HeroAction中的方法为

package com.ABC123.action;

import java.util.ArrayList;
import java.util.List;

import com.ABC123.pojo.Hero;

public class HeroAction {

	private static List<Hero> heroList=new ArrayList<Hero>();

	private  Hero hero;

	private int id;

	static{
		heroList.add(new Hero(1, "德玛", 12, "德玛西亚", "很难哦哦"));
		heroList.add(new Hero(2, "艾希", 45, "德玛西亚", "很厉害的啊"));
		heroList.add(new Hero(3, "亚索", 78, "小学生", "很牛逼"));
	}

	public  String list() {

		return "list";

	}

	//增加
	public  String add() {

		System.out.println(hero);

		heroList.add(hero);
		return "add";

	}

	//删除
	public String del() {

		System.out.println("删除的下标===>"+id);

		Hero hero2 = heroList.get(id);

		System.out.println(hero2);

		heroList.remove(hero2);
		return "add";
	}

	public String goToUpd() {

		Hero hero5 = heroList.get(id);
		System.out.println("该条点击修改的的hero==>"+hero5);

		return "gotoupd";

	}

	//修改
	public String upd() {
		System.out.println(hero.getId());
		int id2 = hero.getId();
		id2-=1;
		System.out.println("id2===>"+id2);

		//修改前
		Hero hero5 = heroList.get(id2);
		System.out.println("该条点击修改的的hero==>"+hero5);

		//接到的值为hero

		hero5.setAge(hero.getAge());

		hero5.setName(hero.getName());

		hero5.setStory(hero.getStory());

		hero5.setZhenying(hero.getZhenying());

//		heroList.set(id2, hero);

		System.out.println("修改后的hero==>"+hero);
		return "add";
	}

	//================================

	public List<Hero> getHeroList() {
		return heroList;
	}

	public void setHeroList(List<Hero> heroList) {
		this.heroList = heroList;
	}

	public Hero getHero() {
		return hero;
	}

	public void setHero(Hero hero) {
		this.hero = hero;
	}

	public int getId() {
		return id;
	}

	public void setId(int id) {
		this.id = id;
	}

}

　　则在JSP中用如下方式调用方法

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
    <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
    <%@ taglib uri="/struts-tags" prefix="s" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<a href="/struts-01/add.jsp">去添加</a>
</br>
</br>
<table border="1">
	<tr>
		<td>id</td>
		<td>name</td>
		<td>age</td>
		<td>zhenying</td>
		<td>story</td>
			<td colspan="2">操作</td>
	</tr>

	<c:forEach items="${heroList }" var="hero">
	<tr>
		<td>${hero.id }</td>
		<td>${hero.name }</td>
		<td>${hero.age }</td>
		<td>${hero.zhenying }</td>
		<td>${hero.story }</td>
		<td><a href="heroAction!goToUpd.action?id=${hero.id -1}">修改</a></td>
	<td><a href="heroAction!del.action?id=${hero.id -1 }">删除</a></td>
	</tr>
	</c:forEach>
</table>

<hr>

<a href="/struts-01/add.jsp">去添加</a>
</br>
</br>
<table border="1">
	<tr>
		<td>id</td>
		<td>name</td>
		<td>age</td>
		<td>zhenying</td>
		<td>story</td>
		<td colspan="2">操作</td>
	</tr>

	<s:iterator value="heroList">

	<tr>
		<td><s:property value="id"/></td>
		<td><s:property value="name "/></td>
		<td><s:property value="age "/></td>
		<td><s:property value="zhenying "/></td>
		<td><s:property value="story "/></td>
	<td><a href="heroAction!goToUpd.action?id=<s:property value='id-1'/>">修改</a></td>
	<td><a href="heroAction!del.action?id=<s:property value='id-1'/>">删除</a></td>
	</tr>
	</s:iterator>

</table>

</body>
</html>

　　第三种方式：通配符（推荐使用）

<action name="heroAction_*" class="com.ABC123.action.HeroAction" method="{1}">
	<result name="list" >/list.jsp</result>
	</action>

　　这里的{1} 相当于传进来字符串进行拼接地址 比如传进来list 拼接为/list.jsp

<action name="heroAction_*" class="com.ABC123.action.HeroAction" method="{1}">
	<result name="{1}" >/{1}.jsp</result>
	</action>

　　

<a href="heroAction_list.action">查询
<a href="heroAction_add.action">增加

　　

heroAction_list.action就会调用heroAction中的list方法 然后跳转到list.jsp

heroAction_add.action就会调用heroAction中的add方法 然后跳转到add.jsp